Catheter movement control

ABSTRACT

An endovascular device monitoring system is provided that determines, based on movement of the endovascular device past a selected reference location, at least one of a movement rate of an endovascular device and position of a distal end of an endovascular device in a body of a patient.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. patent application Ser. No. 15/788,618, filed Oct. 19, 2017, which is a continuation of U.S. application Ser. No. 15/488,911, filed on Apr. 17, 2017, issued as U.S. Pat. No. 9,827,055 on Nov. 28, 2017, which is a continuation of U.S. application Ser. No. 13/799,664, filed on Mar. 13, 2013, issued as U.S. Pat. No. 9,623,211 on Apr. 18, 2017, all of which are hereby incorporated herein by reference in all their entirety for all that they teach and for all purposes.

FIELD

The disclosure relates generally to endovascular devices and particularly to monitoring the use of catheters.

BACKGROUND

Catheters are medical devices that can be inserted into a body cavity, duct, or vessel to treat diseases or perform a surgical procedure. Catheterization, for example, is performed in cardiovascular, urological, gastrointestinal, neurovascular, and ophthalmic applications.

Catheters can allow drainage, administration of fluids or gases, access by surgical instruments, and perform wide variety of other tasks depending on the type of catheter. Catheters can, for instance, include energy emitting devices, such as laser and other radiation emitters, to ablate or cauterize tissue. In most uses, catheter is a thin, flexible tube (“soft” catheter) though catheters are available in varying levels of stiffness depending on the application.

Catheterization is normally performed in a series of steps. An introducer needle is first inserted into the body lumen followed by insertion of a guide wire through the introducer needle and into the lumen. The inserted introducer needle is removed, and an introducer sheath and/or dilator are introduced over the guide wire into the desired position to hold the body lumen open and allow insertion of tools, such as the catheter. The catheter can be introduced through the lumen of the introducer sheath using the wire as a guide.

In many applications, the rate of advancement and/or removal of catheters is important not only to patient safety but also to optimal usage of the catheter. Some catheters require a narrow range of advancement rates for effective performance. Laser catheters, for example, should be advanced at a rate of less than about 1 mm/second. Advancing too quickly can increase risk of injury (such as during superior vena cava during lead extraction), increase the forces acting at the laser sheath tip, and prevent the laser from properly ablating tissue (particularly with a smaller body lumen diameter with rapid catheter advancement). Advancing too slowly and lasing tissue too long can also provide poor results.

SUMMARY

These and other needs are addressed by the various aspects, embodiments, and configurations of the present disclosure. The disclosure is directed generally to an endovascular device monitoring system.

A method, according to this disclosure, can include the step of determining, by a microprocessor executable controller and based on movement of the endovascular device past a selected reference location, one or more of a movement rate of an endovascular device and position of a distal end of an endovascular device in a body of a patient.

A non-transient, tangible computer readable medium or system, according to this disclosure, can include microprocessor executable controller logic that, when executed, determines, based on endovascular device movement past a selected reference location, endovascular device movement rate and/or endovascular device distal end or tip position.

The rate is commonly one or more of velocity and acceleration of an endovascular device component.

The controller can detect, by an endovascular device movement sensor positioned at the selected reference location, displacement of one or more markers associated with the endovascular device.

Endovascular device movement can be determined by any of a number of techniques. Endovascular device movement, for example, can be based on one or more of rotation and displacement of a component mechanically engaged with a portion of the endovascular device; a variation in optical property of light reflected by the markers moving past the selected reference location (the variation being caused by the markers having an optical property different from that of other (intervening) parts of the endovascular device); a variation in magnetic field strength along a length of the endovascular device body (the variation being caused by the markers having a magnetic property different from that of other (intervening) parts of the endovascular device); and reading a radio frequency parameter associated with the markers (which can be an active and/or passive Radio Frequency-Identification (“RFID”) tag).

The endovascular device movement sensor can be positioned on or adjacent to an introducer sheath assembly and/or the endovascular device itself.

The endovascular device movement sensor can be positioned externally or internally to the body of a patient.

When the controller determines that the endovascular device movement rate and/or distal end or tip position is unacceptable, the controller can, via a user interface, notify a user of the unacceptable movement rate and/or distal end or tip position in the body of the patient. Alternatively or additionally, the controller can cause a microprocessor executable endovascular device parameter adjustment module to adjust an endovascular device parameter. The endovascular device parameter can, for instance, be one or more of endovascular device velocity, endovascular device acceleration, endovascular device speed, endovascular device operational state, endovascular device position, and endovascular device energy emission level and/or intensity.

The present disclosure can provide a number of advantages depending on the particular configuration. The endovascular device monitoring system can not only detect and provide feedback to the user, such as whether endovascular device movement is too fast, too slow or just right, but also regulate endovascular device movement, thereby enabling physicians to gauge properly endovascular device movement during a procedure and providing optimal usage of the endovascular device (even for endovascular devices requiring a narrow range of advancement rates for effective performance). The movement of laser catheters, in particular, can be reliably, consistently, and accurately maintained at a rate of less than about 1 mm/second, providing a decreased risk of injury (particularly during superior vena cava during lead extraction), decreasing the forces acting at the laser sheath tip, and preventing the laser from improperly ablating tissue (particularly with a smaller body lumen diameter with rapid catheter advancement). The endovascular device monitoring system can also determine endovascular device distal end or tip position within the patient. This may operate in lieu of or complement an imaging system using radiopaque markers on the endovascular device to track endovascular device distal tip position.

These and other advantages will be apparent from the disclosure of the aspects, embodiments, and configurations contained herein.

As used herein, “at least one”, “one or more”, and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, Band C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together. When each one of A, B, and C in the above expressions refers to an element, such as X, Y, and Z, or class of elements, such as X₁-X_(n), Y₁-Y_(m), and Z₁-Z₀, the phrase is intended to refer to a single element selected from X, Y, and Z, a combination of elements selected from the same class (e.g., X₁ and X₂) as well as a combination of elements selected from two or more classes (e.g., Y₁ and Z₀),

It is to be noted that the term “a” or “an” entity refers to one or more of that entity. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. It is also to be noted that the terms “comprising”, “including”, and “having” can be used interchangeably.

The term “automatic” and variations thereof, as used herein, refers to any process or operation done without material human input when the process or operation is performed. However, a process or operation can be automatic, even though performance of the process or operation uses material or immaterial human input, if the input is received before performance of the process or operation. Human input is deemed to be material if such input influences how the process or operation will be performed. Human input that consents to the performance of the process or operation is not deemed to be “material”.

A “catheter” is a tube that can be inserted into a body cavity, duct, lumen, or vessel. In most uses, a catheter is a thin, flexible tube (“soft” catheter), though in some uses, it is a larger, solid (“hard”) catheter.

The term “computer-readable medium” as used herein refers to any storage and/or transmission medium that participate in providing instructions to a processor for execution. Such a medium is commonly tangible and non-transient and can take many forms, including but not limited to, non-volatile media, volatile media, and transmission media and includes without limitation random access memory (“RAM”), read only memory (“ROM”), and the like. Non-volatile media includes, for example, NVRAM, or magnetic or optical disks. Volatile media includes dynamic memory, such as main memory. Common forms of computer-readable media include, for example, a floppy disk (including without limitation a Bernoulli cartridge, ZIP drive, and JAZ drive), a flexible disk, hard disk, magnetic tape or cassettes, or any other magnetic medium, magneto-optical medium, a digital video disk (such as CD-ROM), any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, a solid state medium like a memory card, any other memory chip or cartridge, a carrier wave as described hereinafter, or any other medium from which a computer can read. A digital file attachment to e-mail or other self-contained information archive or set of archives is considered a distribution medium equivalent to a tangible storage medium. When the computer-readable media is configured as a database, it is to be understood that the database may be any type of database, such as relational, hierarchical, object-oriented, and/or the like. Accordingly, the disclosure is considered to include a tangible storage medium or distribution medium and prior art-recognized equivalents and successor media, in which the software implementations of the present disclosure are stored. Computer-readable storage medium commonly excludes transient storage media, particularly electrical, magnetic, electromagnetic, optical, magneto-optical signals.

“Coronary catheterization” is a generally minimally invasive procedure to access the coronary circulation and/or blood filled chambers of the heart using a catheter. It is performed for both diagnostic and interventional (treatment) purposes.

The terms “determine”, “calculate” and “compute,” and variations thereof, as used herein, are used interchangeably and include any type of methodology, process, mathematical operation or technique.

A “lead” is a conductive structure, typically an electrically insulated coiled wire. The electrically conductive material can be any conductive material, with metals and intermetallic alloys common. The outer sheath of insulative material is biocompatible and biostable (e.g., non-dissolving in the body) and generally includes organic materials such as polyurethane and polyimide. Lead types include, by way of non-limiting example, epicardial and endocardial leads. Leads are commonly implanted into a body percutaneously or surgically.

The term “means” as used herein shall be given its broadest possible interpretation in accordance with 35 U.S.C., Section 112, Paragraph 6. Accordingly, a claim incorporating the term “means” shall cover all structures, materials, or acts set forth herein, and all of the equivalents thereof. Further, the structures, materials or acts and the equivalents thereof shall include all those described in the summary of the invention, brief description of the drawings, detailed description, abstract, and claims themselves.

The term “module” as used herein refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combination of hardware and software that is capable of performing the functionality associated with that element. Also, while the disclosure is presented in terms of exemplary embodiments, it should be appreciated that individual aspects of the disclosure can be separately claimed.

A “non-Newtonian fluid” is a fluid whose flow properties differ in any way from those of Newtonian fluids. Most commonly the viscosity (measure of a fluid's ability to resist gradual deformation by shear or tensile stresses) of non-Newtonian fluids is dependent on shear rate or shear rate history. However, there are some non-Newtonian fluids with shear-independent viscosity, that nonetheless exhibit normal stress-differences or other non-Newtonian behavior. Many salt solutions, suspensions, and molten polymers are non-Newtonian fluids. In a Newtonian fluid, the relation between the shear stress and the shear rate is linear, passing through the origin, the constant of proportionality being the coefficient of viscosity. In a non-Newtonian fluid, the relation between the shear stress and the shear rate is different and can even be time-dependent.

“Radio-Frequency Identification” (RFID) refers to the use of a wireless non-contact system that uses radio-frequency electromagnetic fields to transfer data from a tag attached to an object, for the purposes of automatic identification and/or tracking. Some tags require no battery and are powered and read at short ranges via magnetic fields (electromagnetic induction) (known as passive RFID tags). Others use a local power source and emit radio waves (electromagnetic radiation at radio frequencies) (known as active RFID tags). The tag contains electronically stored information which may be read from up to several meters away. Unlike a bar code, the tag does not need to be within line of sight of the reader and may be embedded in the tracked object.

A “surgical implant” is a medical device manufactured to replace a missing biological structure, support, stimulate, or treat a damaged biological structure, or enhance, stimulate, or treat an existing biological structure. Medical implants are man-made devices, in contrast to a transplant, which is a transplanted biomedical tissue. In some cases, implants contain electronics, including, without limitation, artificial pacemaker, defibrillator, electrodes, and cochlear implants. Some implants are bioactive, including, without limitation, subcutaneous drug delivery devices in the form of implantable pills or drug-eluting stents.

It should be understood that every maximum numerical limitation given throughout this disclosure is deemed to include each and every lower numerical limitation as an alternative, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this disclosure is deemed to include each and every higher numerical limitation as an alternative, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this disclosure is deemed to include each and every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.

The preceding is a simplified summary of the disclosure to provide an understanding of some aspects of the disclosure. This summary is neither an extensive nor exhaustive overview of the disclosure and its various aspects, embodiments, and configurations. It is intended neither to identify key or critical elements of the disclosure nor to delineate the scope of the disclosure but to present selected concepts of the disclosure in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other aspects, embodiments, and configurations of the disclosure are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are incorporated into and form a part of the specification to illustrate several examples of the present disclosure. These drawings, together with the description, explain the principles of the disclosure. The drawings simply illustrate preferred and alternative examples of how the disclosure can be made and used and are not to be construed as limiting the disclosure to only the illustrated and described examples. Further features and advantages will become apparent from the following, more detailed, description of the various aspects, embodiments, and configurations of the disclosure, as illustrated by the drawings referenced below.

FIG. 1 depicts an introducer sheath assembly according to an embodiment of this disclosure;

FIG. 2 depicts a catheter monitoring system according to an embodiment of this disclosure;

FIG. 3 depicts a control algorithm according to an embodiment of this disclosure;

FIG. 4 depicts a control algorithm according to an embodiment of this disclosure;

FIG. 5 depicts a catheter assembly according to an embodiment of this disclosure;

FIG. 6 depicts a catheter assembly according to an embodiment of this disclosure;

FIG. 7 depicts a catheter movement sensor according to an embodiment; and

FIG. 8 depicts a catheter movement sensor according to an embodiment.

DETAILED DESCRIPTION

Endovascular device movement is monitored and/or controlled by an endovascular device monitoring system. The endovascular device monitoring system is commonly automated to avoid human error. While the endovascular device monitoring system is discussed with specific reference to catheters, it is to be understood that it can apply equally to other endovascular devices, such as lead removal or extraction sheaths, needles, surgical instruments, snares, and the like. The endovascular device monitoring system can be used for any type of catheter, including without limitation laser ablation, cauterization, and lead removal catheter systems.

FIG. 1 depicts an introducer sheath assembly 100 for monitoring catheter usage according to an embodiment. The introducer sheath assembly 100 includes a sheath 104 having a sheath lumen 106, a distal tip 108, and proximal end 112. The proximal end 112 includes a side port 116 in fluid communication with a valve 120 and a catheter movement sensor 124. A catheter (not shown) can be introduced through a main port 128 in the valve 120 or side port 116. The main port is coaxial with the lumen 106.

FIG. 5 depicts a catheter assembly 500 for monitoring catheter usage according to another embodiment. The catheter assembly 500 is positioned subcutaneously (underneath the skin 502 of a patient) and includes a catheter body 504 and a catheter movement sensor 124. The catheter movement sensor 124 is an integral part of the subcutaneous portion of the introducer sheath assembly.

FIG. 6 depicts a catheter assembly 600 for monitoring catheter usage according to yet another embodiment. The catheter assembly 600 is positioned subcutaneously and includes a catheter body 504 and a catheter movement sensor 124. Unlike the catheter assembly 500, the catheter movement sensor 124 is an integral part of the catheter assembly. The catheter assembly 600 can be a modified version of a coronary laser atherectomy catheter by the Spectranetics Corporation under the tradenames ELCA™ and Turbo Elite™ (each of which is used for coronary intervention or catheterization such as recanalizing occluded arteries, changing lesion morphology, and facilitating stent placement) or a laser sheath sold under the tradename SLSII™ and GlideLight™ (which is used for surgically implanted lead removal).

The catheter movement sensor 124 in any of the above embodiments can have many different configurations. Velocity, speed, acceleration, and/or position of a catheter can be determined by one or more of mechanical, optical, ultrasound (acoustic), magnetic, electrical, and electromagnetic sensing techniques.

FIG. 7 illustrates an example of a mechanical sensing technique. The mechanical movement sensor 700 includes counter-rotating first and second wheels 704 a,b engaging a catheter body 504 as it advances or withdraws from a body lumen. As will be appreciated, the velocity or rate of movement and position of the catheter body 504 are a function of the rate of rotation of the first and/or second wheel 704 a,b. While position may be tracked using only one wheel engaging the catheter body 504, the frictional forces opposing catheter movement could be higher, thereby creating hindering catheter operation by the physician. Other mechanical techniques will be obvious to those of ordinary skill in the art.

FIG. 8 illustrates an example of a radiation sensing technique in which the catheter movement sensor 124 includes not only a detector but also one or more markers 804 spaced at predetermined intervals 808 (which may be equidistant or non-equidistant) along a length of the catheter body 800. Adjacent markers may be used to start and stop a timer to measure a predetermined time interval required to transgress the intervening predetermined interval 808 and counting the transgressed markers to determine a subcutaneous length or approximate position of the distal tip of the catheter. The markers may be substantially identical or configured differently. An example of the latter is where each marker is detectably encoded (e.g., each marker being configured as a unique or substantially unique bar code) to represent a distance from a selected reference point.

The detector and markers of the catheter movement sensor 124 are typically located on different ones of the introducer sheath 100 and catheter itself. For example, the markers can be located on the catheter body 800 as shown, and the detector on the introducer sheath 100. Alternatively, the marker(s) can be located on the introducer sheath 100, and the detector on or in the catheter.

In the case of optical sensing, the markers 804 can be any marker that reflects light in a detectable and consistent manner. The markers 804 typically have an optical property, such as reflectance (or reflectivity), absorbance (or absorption), and the like, different from that of the intervening catheter body 800. A light source emits modulated or unmodulated light onto the catheter body 800 as the body 800 moves. Light reflected along a length of the catheter body 800 is captured by the detector typically configured as an array of photoelectric devices. The detector dissects the reflected light into its various spectra. The differing optical properties of the light reflected by the markers when compared with the intervening body 800 are translated into an electric signal, which is output to a controller.

In the case of magnetic sensing, the markers are magnetic or have a magnetic property different from that of the intervening catheter body 800. The detector can be a magnetic field sensor, such as a rotating coil, Hall effect magnetometer, NMR magnetometer, SQUID magnetometer, or fluxgate magnetometer that can measure variations in magnetic field strength along a length of the catheter body 800 and thereby locate the markers. The measured magnetic field variations when compared with the intervening body 800 are translated into an electric signal, which is output to a controller.

In the case of ultrasonic sensing, the markers have a different ultrasonic transmission property than the intervening catheter body 800. An ultrasound transducer can act both as the ultrasonic emitter and detector to detect reflected or transmitted ultrasonic energy and thereby locate the markers. An electrical signal is generated when each marker passes the detector, which signal is output to a controller.

In the case of sensing using other wavelengths of radiation (such as x-rays), the markers can include a radiopaque material, such as gold or other metal, while the intervening catheter body 800 includes a radiolucent material, or vice versa, such that the markers have a different imaging property than the intervening catheter body 800. An electrical signal is generated when each marker passes a conventional detector, which signal is output to a controller.

In the case of electrical sensing, the markers are electrically conductive or have an electrical conductivity or resistivity different from that of the intervening catheter body 800. An electrical parameter, such as voltage, current, resistance, or ambient electric field can be detected to determine marker location. The detector, for example, can be a voltmeter, ammeter, magneto resistive field sensor, Hall Effect current sensor transducer, potentiometer, oscilloscope, LCR meter, and the like. An electrical signal is generated when each marker passes the detector, which signal is output to a controller.

An example of sensing using a combination of electromagnetic energy and electrical sensing is radio-frequency identification. The markers can be configured as active or passive RFID tags. In one configuration, the markers are configured as passive RFID tags, and the detector as an active or powered RFID reader. In another configuration, the markers are configured as active RFID tags, and the detector as an active or passive RFID reader.

As will be appreciated, the above discussion presents examples only and is not intended to be exhaustive. One of ordinary skill in the art will appreciate that other sensing techniques can be employed depending on the application.

FIG. 2 depicts a catheter monitoring system 200 according to an embodiment. The catheter monitoring system 200 includes the catheter movement sensor 124 in signal communication with a controller 204, which is, in turn, in signal communication with a user interface 208 and a catheter parameter adjustment module 212. The controller 204 executes one or more microprocessor executable control algorithms stored in a computer readable medium to receive catheter movement signals from the catheter movement sensor 124 and, based on the received catheter movement signals, provide alarm and other output to the user via user interface 208 and/or effect catheter parameter adjustment via the catheter parameter adjustment module 212. The user interface can provide audible (e.g., sounds), tactile, and/or visual (e.g., lights) output to the user and receive user commands as input to the controller 204. Audible, tactile, and/or visual output relates to one or more of catheter movement and/or catheter distal tip location within the body lumen. The catheter parameter(s) adjusted by the catheter parameter adjustment module 212 include one or more of catheter velocity, acceleration, speed, operational state (e.g., on or off), catheter energy emission level or intensity, catheter (distal end) position, and the like.

Catheter parameter adjustment or regulation can be affected by various techniques. Catheter velocity, acceleration, and/or speed can be adjusted by selectively and/or variably increasing resistance to catheter movement, such as by hydraulic resistance applied to the catheter or a part thereof, frictional resistance applied to the catheter or a part thereof by a braking system, resistance posed by movement of the catheter or a part thereof through a non-Newtonian fluid (such as Dilitant), resistance created by movement of a magnetic material associated with the catheter through an external magnetic field (which may be from a magnet or flow of charged particles), and other means of slowing or retarding catheter movement. Catheter operational state can be controlled or regulated by turning an energy emitter in the catheter on or off, catheter energy emission level or intensity can be controlled or regulated by altering a degree of energization of a power source of the energy emitter.

An operation of the controller 204 will now be described with reference to FIG. 3.

Operation commences when the controller 204 senses a stimulus in step 300. The stimulus, for example, can be receipt of user input, receipt of a catheter movement signal from the catheter movement sensor 124, passage of time, and the like.

In step 304, the controller 204 selects a spatial increment over which to determine catheter velocity, acceleration, and/or speed and, if necessary, a reference location at which to detect, track or otherwise observe marker movement. A typical selected spatial increment is the spatial interval between adjacent markers 804, though the selected spatial increment can span more than two increments depending on the application. Differently sized spatial intervals can be selected for different types of procedures and/or catheters. Typically, the reference location is the location of the catheter movement sensor 124 or a component thereof.

In step 308, the controller 204 determines the time interval required for the catheter to traverse the selected spatial increment. The time interval can be determined, for example, by initiating or reading a start time on a timer (not shown) when a first marker passes a detector and terminating or reading a stop time on the timer when the marker associated with the end of the selected spatial increment passes the detector.

In optional step 312, the controller 204 determines a catheter movement rate (e.g., velocity, acceleration, and/or speed) and/or distal tip position (based on the number of markers that have transgressed the detector). Depending on the application, this step may be unnecessary where the time interval is mapped directly to a lookup table showing acceptable and unacceptable time intervals and/or the number of transgressed markers is mapped directly to the subcutaneous length of the catheter and therefore the approximate catheter distal tip position.

In step 316, the controller 204 retrieves predetermined catheter movement and/or catheter distal tip position thresholds. The predetermined thresholds can have a corresponding rule regarding a response if the predetermined threshold is triggered. The rule, for example, can be to provide audible, tactile, and/or visual output to the user, alter a catheter parameter, and/or regulate a catheter movement rate.

In decision diamond 320, the controller 204 determines, based on a comparison of a predetermined threshold to the determined catheter movement rate and/or determined time interval and/or catheter distal tip position, whether catheter movement and/or position is/are acceptable. When acceptable, the controller 204 proceeds to step 324 and optionally notifies the user accordingly. When unacceptable, the controller 204 proceeds to step 328 and initiates a warning to the user and/or alters/controls one or more catheter parameters as described previously. After completing steps 324 and 328, the controller 204 returns to and repeats step 308.

A further operation of the controller 204 will now be described with reference to FIG. 4. The operation is based on user selection between an assisted and unassisted mode of operation. The assisted mode of operation enables the controller not only to provide audible, tactile, and/or visual feedback to the user but also regulate one or more catheter parameters. The unassisted mode of operation enables the controller to provide audible, tactile, and/or visual feedback to the user but not to regulate one or more catheter parameters.

In step 400, the controller 204 senses a stimulus, including those indicated above.

In step 404, the controller 204 determines a current mode of operation. The current mode of operation is typically selected by the user but can default to an assisted mode when catheter operation is unacceptable.

In step 408, the controller 204 determines that the current operating mode is the assisted mode and, in response, controls a rate of catheter advancement or removal using any of the techniques noted above.

In step 412, the controller 204 determines that the current operating mode is the unassisted mode and, in response, monitors the rate of catheter advancement or removal and provides appropriate audible, tactile, and/or visual output to the user.

A number of variations and modifications of the disclosure can be used. It would be possible to provide for some features of the disclosure without providing others.

For example, in one alternative embodiment, the teachings of this disclosure are used with an unpowered catheter mounting any one or more of a variety of tools, such as dilation balloons, cutting balloons, cutting blades, drug release mechanisms, imaging devices, blood flow sensors, contrast media, and the like.

The present disclosure, in various aspects, embodiments, and configurations, includes components, methods, processes, systems and/or apparatus substantially as depicted and described herein, including various aspects, embodiments, configurations, sub combinations, and subsets thereof. Those of skill in the art will understand how to make and use the various aspects, aspects, embodiments, and configurations, after understanding the present disclosure. The present disclosure, in various aspects, embodiments, and configurations, includes providing devices and processes in the absence of items not depicted and/or described herein or in various aspects, embodiments, and configurations hereof, including in the absence of such items as may have been used in previous devices or processes, e.g., for improving performance, achieving ease and\or reducing cost of implementation.

The foregoing discussion of the disclosure has been presented for purposes of illustration and description. The foregoing is not intended to limit the disclosure to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the disclosure are grouped together in one or more, aspects, embodiments, and configurations for the purpose of streamlining the disclosure. The features of the aspects, embodiments, and configurations of the disclosure may be combined in alternate aspects, embodiments, and configurations other than those discussed above. This method of disclosure is not to be interpreted as reflecting an intention that the claimed disclosure requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed aspects, embodiments, and configurations. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the disclosure.

Moreover, though the description of the disclosure has included the description of one or more aspects, embodiments, or configurations and certain variations and modifications, other variations, combinations, and modifications are within the scope of the disclosure, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative aspects, embodiments, and configurations to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter. 

What is claimed is:
 1. A system comprising: a sheath; a laser catheter configured to move relative to the sheath, wherein the laser catheter comprises a distal tip, and wherein the sheath or the laser catheter comprises a sensor configured to sense a position of the distal tip of the laser catheter relative to the sheath; and a controller comprising a non-transient, tangible computer readable medium including logic, whereupon execution of the logic, the controller receives a selection signal to operate in either an assisted mode or an unassisted mode: (A) whereupon the controller being in the assisted mode and receiving a signal indicative of the position of the distal tip, the controller is configured to regulate an operational parameter of the laser catheter; and (B) whereupon the controller being in the unassisted mode and receiving the signal indicative of the position of the distal tip, the controller is configured to provide feedback to a user and configured not to regulate the one or more operational parameters.
 2. The system of claim 1, wherein the operational parameter is an operational state of the laser catheter.
 3. The system of claim 2, wherein the operational state of the laser catheter is on.
 4. The system of claim 2, wherein the operational state of the laser catheter is off
 5. The system of claim 1, wherein the operational parameter is an emission of laser energy by the laser catheter.
 6. The system of claim 1, wherein the operational parameter is an intensity of laser energy by the laser catheter.
 7. The system of claim 1, wherein the feedback comprises audible, tactile or visual feedback.
 8. The system of claim 7, wherein the feedback comprises audible feedback.
 9. The system of claim 8, wherein the feedback further comprises tactile or visual feedback.
 10. The system of claim 7, wherein the feedback comprises tactile feedback.
 11. The system of claim 10, wherein the feedback further comprises audible or visual feedback.
 12. The system of claim 7, wherein the feedback comprises visual feedback.
 13. The system of claim 8, wherein the feedback further comprises audible or tactile feedback.
 14. The system of claim 1, wherein the operational parameter is a movement rate of the laser catheter.
 15. The system of claim 14, wherein the operational parameter comprises a velocity of the laser catheter.
 16. The system of claim 14, wherein the operational parameter comprises an acceleration of the laser catheter. 